More particularly, the invention relates to a sensor comprising:                a housing defining an internal volume that is internal to the housing;        a movable part situated inside said internal volume of the housing;        detector means for detecting a movement of said movable part relative to the housing;        transfer means passing through a first opening in the housing and arranged to act from a first external zone external to the housing to cause said movable part situated inside said internal volume to move; and        first sealing means arranged relative to the housing and to the transfer means to oppose fluid passing from the first external zone external to the housing towards said internal volume of the housing via said first opening of the housing.        
Such a sensor may be subject to malfunction when its internal volume is subjected to large variations of pressure, in particular as a result of leakage through the first sealing means of the sensor.